Spatial audio processor and a method for providing spatial parameters based on an acoustic input signal

Abstract

A spatial audio processor for providing spatial parameters based on an acoustic input signal has a signal characteristics determiner and a controllable parameter estimator. The signal characteristics determiner is configured to determine a signal characteristic of the acoustic input signal. The controllable parameter estimator for calculating the spatial parameters for the acoustic input signal in accordance with a variable spatial parameter calculation rule is configured to modify the variable spatial parameter calculation rule in accordance with the determined signal characteristic.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS[0001]This application is a continuation of copending International Patent Application No. PCT / EP2011 / 053958, filed Mar. 16, 2011, which is incorporated herein by reference in its entirety, and additionally claims priority from European Patent Application No. EP 10186808.1, filed Oct. 7, 2010 and U.S. Patent Application No. 61 / 318,689, filed Mar. 29, 2010, all of which are incorporated herein by reference in their entirety.BACKGROUND OF THE INVENTION[0002]Embodiments of the present invention create a spatial audio processor for providing spatial parameters based on an acoustic input signal. Further embodiments of the present invention create a method for providing spatial parameters based on an acoustic input signal. Embodiments of the present invention may relate to the field of acoustic analysis, parametric description, and reproduction of spatial sound, for example based on microphone recordings.[0003]Spatial sound recording aims at capturin...

AI Technical Summary

Benefits of technology

[0013]According to another embodiment, a method for providing spatial parameters based on an acoustic input signal may have the steps of determining a signal characteristic of the acoustic input signal; modifying a variable spatial parameter calculation rule in accordance with the determined signal characteristic; calculating spatial parameters of the acoustic input signal in accordance with the variable spatial parameter calculation rule; and determining a stationarity interval of the acoustic input signal and modifying the variable spatial parameter calculation rule in accordance with the determined stationarity interval, so that an averaging period for calculating the spatial parameters is comparatively longer for a comparatively longer stationarity interval and is comparatively shorter for a comparatively shorter stationarity interval; or selecting one spatial parameter calculation rule out of a plurality of spatial parameter calculation rules for calculating the spatial parameters in dependence on the determined signal characteristic.

[0015]It is an idea of embodiments of the present invention that a spatial audio processor for providing spatial parameters based on an acoustic input signal, which reduces model mismatches caused by a temporal variance of the acoustic input signal, can be created when a calculation rule for calculating the spatial parameter is modified based on a signal characteristic of the acoustic input signal. It has been found that model mismatches can be reduced when a signal characteristic of the acoustic input signal is determined, and based on this determined signal characteristic the spatial parameters for the acoustic input signal are calculated.

[0016]In other words, embodiments of the present invention may handle the problem of model mismatches caused by a temporal variance of the acoustic input signal by determining characteristics (signal characteristics) of the acoustic input signals, for example in a preprocessing step (in the signal characteristic determiner) and then identifying the signal model (for example a spatial parameter calculation rule or parameters of the spatial parameter calculation rule) which best fits the current situation (the current signal characteristics). This information can be fed to the parameter estimator which can then select the best parameter estimation strategy (in regard to the temporal variance of the acoustic input signal) for calculating the spatial parameters. It is therefore an advantage of embodiments of the present invention that a parametric field description (the spatial parameters) with a significantly reduced model mismatch can be achieved.

Problems solved by technology

However, a problem that commonly arises is that different audio signals can exhibit a significant temporal variance such that a general time-invariant model describing the audio input is often inadequate.

In particular, when considering a single time-invariant signal model for processing audio, model mismatches can occur which degrade the performance of the applied algorithm.

As mentioned before, if this is not the case model mismatches arise, which usually leads to severe errors in the estimates.

Such model mismatches represent a recurrent problem since acoustic input signals are usually highly time variant.

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